Sewing machine



April 29, 19%o 1,492,133

J. KIEWICZ sEwING MACHINE Filed April 15 1921 2 Sheets-Sheet 1 invenToT.

John yMievvic bywMW 72 I Afiys.

April 29 1924.. 1,492,133

J. K|EW|CZ- SEWING MACHINE Filed April 1'5, 1921 2 Sheets-Sheet 2 Patented Apr. 29, 4

UNHTEB STTES AWJM PATENT FFIQE.

JHN KIEWICZ, OF BOSTO'N, MASSACHUSETTS, ASSIGNOR TO THE REF-CE BUTTON HOLE MACHINE COMPANY. OF BOSVTON, MASSACI-IUSETTS, A CORPORATION OF MAINE.

SEWINGrl MACHINE.

Application filed April 15, 1921. Serial No. 461,5161

To all whom it may concern:

Be it known that I, JOHN KIEWICZ, a citizen of the United States, and resident of Boston, county of Suffolk, State of Massachusetts, have invented an Improvement in Sewing Machines, of which the following description, in connection with the accompanying drawing, is a specification, like characters on the drawing representing like parts.

This invention relates to two-thread sewing machines of the type Which are constructed to sew a short seam and then come to rest, such for instance, as a button-hole se'wing machine, and it particularly relates to the means for pulling off a length of under thread at the end of'the button-hole so as to provide a sufi'icient length of under thread for forming the first stitch on tht n ext button-hole and for trimming the threac and stay cord.

One feature of the invention is a novel pull-oli' device which acts on the under thread between the throat plate Vand the tension for the under thread and which is operative to pull off a length of under thread I through the tension While the last stitches are being formed on the button-hole, the amount of thread thus pulled off being sufiicient to insure the proper formation of the first stitching at the beginning of the next button-hole.

Another feature of the invention is a novel thread trimming elementy Which becomes operative after the stitch-forming mechanism has come to rest and after the above mentioned pull-ofi device has drawn off the length of under thread through the tension. The trinnning device is constructed to draw through the throat plate the length of under thread Which has been previously pulled through the tension by the pull-off and then to cut said under thread close to the work thereby leaving the necessary amount of under thread projecting through the throat plate to insure the proper formation of the first stitch on the next succeeding button-hole.

These two features of the invention cooperate to draw off the length of under thread in 'two stages, the first ystage consisting in dra'wing the underithread through the tension by the pull-off and the second stage consisting in drawing the pulled-off length of under thread through the throat plate. The advantage of this two stage operation is that it reduces to a minimum the liability of breaking or severing' the under thread as it is drawn through the throat plate by the thread trimming device, for if' the desired length of under thread Were pulled off at one operation the tension on the thread would often be such as to cause the thread to break.

Another feature of my invention relates to a novelv form of pull-off device which is mounted on the turret that supports the under thread mechanism and is operated by the turning movement of the turrent during the formationA of the barring stitchesy at the end of the button-hole. One advantage of this construction and operation is that the act of drawing the under thread through the tension while the last stitches are being formed results in providing an additional tension on the thread at the stitch-forming point so that the barring stitches are set more tightly than if the pulling-ofi:7 operation Were not being performed simultaneously with the formation of the stitches.

As stated above the thread-trimming device is constructed to draw through the throat plate a length of under thread before severing the thread and at the same time a length of stay cord is drawn through the throat plate leaving a suflicient length of stay cord projecting fromrthe throat plate to insure the proper stitching operation at the beginning of the next button-hole. My improved thread trimmer operates at rthe end of the button-hole to cut not only the end of the stay cord extending to the source of supplyT but also the end of the stay cord which projects at the point where the stitching on the buttoirhole began.

In order to give an understanding of my invention I havelillustrated it as it might be applied to a button-hole sewing machine of the Beece type, e'xemplifications of which are found in United States Patents No. 1,188,942, June 27, 1916, No.l 1,188,944, June 27, 1916, No. 1,338,373, April 27 1920, No. 1,361,871, Dec. 14, 1920, but inasmuch as the invention relates simply to the mechaand trimming it and the ystay cord I have i shown in the drawings only such portions per' .thread-handling mechanism. V-

overhanging arm omitted. '-1

of Va Reece button-hole sewing machine as are necessary to give an understanding, of the invention. V

In the drawings: Fig. 1 is a'side view of a portion of a button-hole sewing machine having my improvements applied thereto. v

Fig. 2 is a front view of Fg. l with the Fig. 3 is a plan view of the clamp plate and the portion of theA bed frame showing my Aimproved' thread 'trimming device.

: Fig. lis a section on the line M, Fig. 3. V F.i'g.r5 Ais a section on the line 5-5, Fig. 3. "Fig; 6 is va section on the line 6-6, Fig. 3. V Fig. 7 is an enlarged .horizontal view through the turret. V

Fig. 8 is a detail of the pull-off lever. :Fig 9 is a view of a Vbutton-hole just at its completion and showing the threads which are trimmed by the mechanism Vherein described. i

l-indicatesv aportion of the bed .frame of fa button-hole sewing machine from which risesthe overhanging arm2 carrying the up- Such mechanism comprises the usual needle bar 3-which supports the upper needle-4 which lcontrolslthe upper thread 5,v said needle bar having a vertical reciprocation in the overhangng arm as usual.

v vThe-under thread is indicated at 6V and it is manipulated by an under-thread-hand ling mechanism situated beneath the bed frame 1 Vand carried by a turret 7 Which is rotatably mounted in bearings carried by;

the depending portionV 8 of the sewing machine frame. This turret'as well as the Vupper needle is constructed to be rotate'd when sewing around the ends ofthe button-hole as usual in sewing machines of this type, and

such rotation is herein provided for by the rock shaft V9 carrying the segment gears 10 that mesh with gears 11 and-12on the needle bar 3 and turret 7 respectively, the rock sha-ft 9 being oscillated at theproper times by the main cam 77 all as usualfinrbutton-V hole Vsewing machines* of this'type.

The turret 7 "s provided'wi h he usual hollow spindle 2 through which the :under thread 6 extends, said thread passing through a slot 13 formed in the spindle and around a tensionll carried byV the turret.V

i From the tensionthey underv thread passes through a guidey eye 15 in the 'turret and Vthence extends to-Vthe needle of the underthread-handling mechanism. The turret plate 16 which is situated beneath the sew- V'ing Lopening 17 in the clamp plate' 18 that is mova'bly carried b-y'thebedframe 1 of the V the work w and the latter'is held in position during the stitching on the Vbutton-hole by the usual clamps 19.

The parts thus far described are, or may' be, all as Uusual in button-hole .sewng machines and form no vention. v V,

As stated above one feature of my invention relates to .a novel pull-off device acting on the under thread 6 betweenV the throat plate16 andtension 14 and Operating to .draw off. a lengththereof fromL the source part of my present inof supply while the last stitches are being formed on the button-hole, the length Ithus drawn off being' suflicent to provide vfor the proper formation of the first stitch on the next button-hole. .The length of threadver 20 which ispivotedflto a block 21L Secured to the turret, said lever having at its upper i end. a guide eye 22 whichis normally situated between-the eye 15.-in the turret and under thread that extendsibetween the tension and the guide eye 15 passes through thev guide eye 22.V ThisV-pull-off lever 20 Visl nor- VV 'the tension 14 so that the portion of the I mally held in its operative position against 'v a-stop 23 by means of a spring 24. The vlever is provided at its lower Vendwith a V ger 25 Which is situated to be 'actuated by aVV cam 26 carried by the Vportion' 81 of the frame.. During the stitching along the sides of the button-holeand around 'the eye end of the button-hole the' turret will be so positioned that the Vfinger 25 of the .pull-off lever is outV of engagement with the cam 26. When, however, the button-hole is just being completed the turret will be turnedso as to cause the stitchingto stitchacrossfthe end y127 of the 'button-hole. During this turning movement yof the turret theJ finger I25 engages thecam i i' V V 26 and causes the pull-OH4 arm 20 to swing about its pivot thus drawing ofl" .a' length of under thread between the tension ltV and the guide 1.5. This pulling off of alength ofV under thread occurs while the stit'chesfl'areV Vbeing formed at the end of the button-hole and When the stitch-forming mechanism comes'to rest the .pull-off lever will be in its eration of drawingofi' .a 'length of'un'de'r youtward position shown in Fig. 1. .This opthread occurs before the stitch-forming V mechanism comes torest and while theVlastV stitches on the'button-hole arezbeing formed.

This .is fan advantage because' the tension caused* by ypulling 'off vthe length Vof under rer-9243:11

thread augments the usual tension on the under thread so that the last stitches will be set tighter than would be the case if the under thread Were subjected only to the tension produced by the tension device 14.

The stitch-forming mechanism comes to rest with the turret substantially in the position shown in Figs. 1, 2 and 7 and during the subsequent operation of the machine by Which the work is carried to button-hole-'cutting posiiton and the button-hole is cut the turret is reversed in its movement to carry the finger 25 out of engagement With the cam 26 thus allowing the pull-off finger to be returned to its normal position.

My invention also includes a novel thread trimming device operatingtto draw through the throat plate the length of under thread Which has been pulled off by the pull-ofi lever 20 and also a length of sta-y cord and then to trim the stay cord and thread close to the Work after the stitch-forming mechanism has come to rest. These operations of drawing the under thread and stay cord through the throat plate and trimming the latter is accomplished by a thread trimming member 27 which is pivoted at 28 to the clamp plate 18. This thread-cutting knife 27 is provided at its end with a notch 29 having a flaring throat 30. This cutter is situated above and close to the clamp plate 18 and is beneath the work. The notch is so situated that as the trimmer swings from the full to the dotted line position the threads which extend from the Work down through the throat plate, (such threads including the under thread, the stay cord Which is laid around the edge of the buttonhole, and also the loop of upper thread extending from the work around the looper), Will be gathered into the notch 29 and carried thereby laterally to one side of the throat plate thus drawng through the throat plate the length of under thread which was pulled off by the lever 20 and also a length of stay cord, such threads and stay cord being cut close to the work after having been drawn through the throat plate. This cutting or trimming of the thread is accomplished by the cooperation of a shearing plate 31 Secured to the clamp platel8 and provided With a shearing edge 32 situated at one side of the throat plate and against which the threads are carried by the Swinging movement of the member 27.

The notch 29 in the trimming member 27 is relatively narrow and the purpose of making it in this Way is to prevent the possibility of the work or barring stitches being cutby the thread trimming operation.

It will bo understood that the thread trimming voperation does not occur until after the stitch-forming mechanism has come to 'rest and the work clamps 19 have released the work, and it will be also understood that the member 27 swings beneath the work and in substantial contact therewith so that the threads will be engagedV in the notch 29 at substantially the point where they leave the work. The Work is normally in position so that the point from which the threads extend downwardly is situated directly over the throat plate 16- and when the thread trimmer swings into the dotted line position it will carry the Work laterally With it after the threads have entered the notch 29. Such lateral movement of the work will draw the stay cord and under thread through the throat plate and the tension on the stay cord Will tend to pull the work downwardly f i:

against the upper side of the cutting element 27. The notch or slot 29 is so narrow, however, that the work will not be pulled down into it by the tension on the threads as they are pulled through the throat plate and therefore there is no danger that the Work will be drawn downwardly by such tension into a position where either the work or the barring stitches will be cut by the shear edge 32. This device therefore operates to cut the threads close to the work Without danger of injuring the button-hole stitching.

The thread trimming device is arranged to pass beneath the shear plate 31 and the latter is provided With a guiding finger 38 which rides up the inclined portion 39 of the member 27 and acts to guide the cutting member in its movement.

From the above description it will be obvious that When the threads are severed there will be projecting from the throat plate not only a length of under thread but also a length of the stay cord. These ends Will be left proj ecting from the work when the next button-hole is stitched so that at the completion of the next button-hole there will be an end 41 of stay cord projecting from the under side of the work as shown in Fig. 9. The thread trimming device is constructed so that When it swings into the dotted line position it will gat-her into the notch 29 not only the stay cord 50 extending from the work to the source of supply and the under thread but also the projecting end 41 of the stay cord and all these ends Will be cut close to 1the Work thus making a finished buttonho e.

The cutter 27 is provided with the inclined under face 42 which assists in guidng the end 41 of the stay cord into the notch 29.

The means herein provided for actuating the thread trimming member 27 is an actuating lever 33 pivoted to the machine frame at 34 and operated by a cam 35 rigid with the main cam all as shown in my Patent No. 1,361,87l, Dec. 14, 1920. The trimmer 27 is extended beyond the pivot 28 and is provided With a curved slot 34 forming on one side a cam face 35 and on the opposite side another cam face 36. The end of the llf) the headiof the pivot screw 28 'and .the meini i ber'l2l7, said friction washer applying' sufficient friction tothe member 27 to insure by the 'lever 33.

its remaining in any position in which itv may be left untilit isfpositively actuated lclaim; i i

:1. In asewmgmachmeconstructed to sew -a short seam and then-come to rest, the combinationflwith stitch forming mechanism vconstructed to concatenate an upper and an under thread, of a tension device for the under thread,*and means operative during the formation of the finalV stitches'of the seam and before the last stitch isl begun to draw a length of under thread -from the.

source of supply'through saidtension device. i i '2. In a two-thread sewmg Vmachine constructedV to sew a short seam: and then come i to rest, the combination with stitch-formi ing :mechanism constructedV to concatenate an .upper and-an under-thread, of aiten'sion device, for the under thread, means acting on thev underthread V'while a plurality of thefinal stitchesfof the seam are being made to draw through thetension devicea length of under thread sufficient to insurethe formation of the first stitch of the next seam.

f 3. In a sewing machine constructed to sew Va short seam and then come to rest, the i Vcombination with stitch-formingfmechanism,

i i ofaptens'ion-deviceforthe under thread,

means operative during the formation of a pluralitylj-of the final stitches of the seam to draw-through the tension device a-length V ofunder thread, and means to cut the thread close :to the work.v i i i Vaveln a Vtwo-thread lsewing machine constructed to vsew 'a' short seam and then come to rest, the combination'with stitch-forming mechanism constructed tofconcatenate'jan upper Vand an under thread, of a tension :de-

f vice for kt-heunder thread, means acting on the under thread and operative during the formation ofa plurality of the final-stitches ofthe seamtodraw through the tension 'device a length :of under thread suflicient to i insure the formation of the first stitch of the next seam, and means to fcutthe under thread close to the Work. i -5.V Ina button-hole seWing machine, the combination with stitch-forming mechanism Vincluding therunder thread mechanism, of

afrotatable 'turret on which said under threadV .mechanism ist. Suprertesit. 2 .thread tension device on the turret,.means torotate theV turret in'lsew'ing aroundy the end ofthe button-hole,v and means actuated by said rotation vof the ytur-ret as the Ystitching onrthe button-hole lis beingy completedV to draw i through the tensionV deviceV and from vthe source of supply -a .length of under Ythread suflicent to insure the properV formation of the first stitch on'the next button-hole.

' V6. In :a button-hole sewing machine, the combination with stitch-forming mechanism including the under thread mechanism, of a I r'otatable turret Von which' said I under thread inechanism'is supported, means Ato i rotate the turret in sewing around the-end of the button-hole, means, actuated'by :the

rotation of the turret to draw loffra length of under thread from the source ofV supply during the formationL of the'last stit'c'hes on the button-hole and means to cut the thread' close to thework. U v i, ir. 7. In a button-hole sewing machine, the combination with a frame, of a turretro? tatably-mounted thereon, under thread manipulating mechanism carried by said turret, a* pull off leverv pivoted to'saidV turretV andacting on the under thread, 'and means to actuate said 'lever-by vthe turning Vmovement of the turret during the formation of the final stitcheson the button-hole thereby to pullV ofiV a length of under thread; from i the source of supply. i i v 8,111 abutton-hole sewing machine, the combination with a Vtatably mountedfthereon, under thread mafraine, of a turret ro- V ice nipulating mechanism carried bysaid'y turret, Va pull off lever. pivoted to saidturret and acting ony the under thread, and a cam carried by 4the frameand situated to engage said lever as the -turret turns during the formation of the finalstitches of the button-hole thereby to drawflofl' a length of unf v der thread.

V9,. 'Ing a button-hole sewmgV machine, the combination with a frame, of a turret roytatably mounted thereon and p'rovided'with throat plate, under thread mechanism car- Vried by the turret, a tension for the under thread mounted on the turret, means operative during' the formation of the last Vstitches under thread between the throat plate and tension, means operative Vafter the stitchforming mechanism has come to rest to draw said lengthy of under thread through the throatplate and to cuty itl close to the work.

10. Ina button-hole sewing machine, the combination with a frame, of a turret rotatably mounted thereon and having a throat plate, under thread mechanismcarried by Vof thebutton-hole to draw off La length of the turret, a tension for the underthread, i

means-to rotate they turret during the formation of the final stitches on the button-hole, means rendered; operative by such rotation Ofthe turret todraw a lengthof 'underV thread between the throat plate and tension, and means operative after the stitch-forming mechanism has come to rest to draw said length of under thread through the throat plate and sever the latter close to the work.

11. In a button-hole sewing machine, the combination with a frame, of a turret rotatably mounted thereon and having a throat plate, under thread mechanism carried by the turret, a tension for the under thread, means to rotate the turret during the formation of the final stitches on the button-hole, means rendered operative by such rotation of the turret to dra-W off a length of under thread between the throat plate and tension, and means operative to draw through the throat plate said length of under thread and a length of stay cord and to sever said thread and stay cord.

12. In a button-hole sewing machine, the combination with a frame, of a turret rotatably mounted thereon and provided with a throat plate, under thread mechanism carried by the turret, and tension for the under thread, means carried by the turret and operative during the formation of the last stitches to draw ofi a length of under thread between the throat plate and tension, means operative after the stitch-forming mechanism comes to rest to draw through the throat plate said length of under thread and a length of stay cord and to cut both close to the work.

13. In a two-thread button-hole sewing machine, the combination with work-holding means including a clamp plate on which the work is supported of a throat plate beneath the clamp plate and through which the under thread passes, a shear plate stationarily carried by the clamp plate and situated at one side of the throat plate, a

thread-trimming member pivoted to they clamp plate and Operating between the shear plate and the clamp plate, said thread-trimming member having a notch which is arranged to receive the threads extending from beneath the work as said trimmer is moved toward the throat plate, and means to actuate said trimming member, the relative position of the shear plate and throat plate being such that the notched end of the thread-trimming member is carried across the throat plate in its travel toward the shear plate, whereby the threads gathered into the notch are drawn through the throat plate, said notch being relatively long and narroW and having sutficient width to receive the threads but of such narrow dimensions that the work cannot be drawn into it by the tension on the threads as said threads are being drawn through the throat plate.

14. In a sewing machine constructed to sew a short seam and then come to rest, the combination with stitch-forming mechanism, of means operative only during the formation of the final stitches of the seam and before the last stitch is begun to draw oif a length of thread from the source of supply.

15. In a sewing machine constructed to sew a short seam and then come to rest, the combination with stitch-forming mechanism of means operative only during the formation of a plurality of the final stitches of the seam to draw oif a length of thread from the source of supply, and means to cut the thread close to the work.

In testimony whereof, I have signed my name to this specification.

JOHN KIEWICZ. 

